Reservoir engineering using quantum optimal control for qubit reset

@article{Basilewitsch2019ReservoirEU,
  title={Reservoir engineering using quantum optimal control for qubit reset},
  author={Daniel Basilewitsch and Francesco I. Cosco and Nicolino Lo Gullo and Mikko M{\"o}tt{\"o}nen and Tapio Ala-Nissil{\"a} and Christiane P. Koch and Sabrina Maniscalco},
  journal={New Journal of Physics},
  year={2019},
  volume={21}
}
We determine how to optimally reset a superconducting qubit which interacts with a thermal environment in such a way that the coupling strength is tunable. Describing the system in terms of a time-local master equation with time-dependent decay rates and using quantum optimal control theory, we identify temporal shapes of tunable level splittings which maximize the efficiency of the reset protocol in terms of duration and error. Time-dependent level splittings imply a modification of the system… 

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